Lightning-arrester.



'-.Ffzgl'sf N F. In. BuKHART.

LIGHTNINGAABRESTER.: APPLICATION FILED DIAR- 6, lI/9J7..

1,245.7 1 2'. l Patented Nov.. 1.3,. 1917.

ATTORNEY FREDERICK H. BURKHART, or Trinitron, NEW JERSEY.'

LIGHTNING-ARRESTER.

Specification of Letters Patent.

atentcd ov. 13. 1.917.

Application filed March 6, 1917. Serial No. 152,630.

Be it known that I, FREDERICK I-I. BURK- iLvRr, a citizen of United States, residing at 435 Princeton avenue, Trenton, in the county of Mercer and State of New Jersey, have invented new and useful Improvements in Lightiiing-Arresters, of which the following in a specification.

This invention relates to lightning arrcsters, and has for an object to provide an etlicient and practical device adapted for service in protecting electrical circuits, and more particularly the instruments carried thereby, from the damaging'etfects of lightning, and other high potential currents.

Another object of the invention resides in a device of the above character, wherein is .embodied a conductor strap having opposed terminals thereof connected with the. wires of an electrical circuit, portions of the strap being substantiallyv arched, and are slightly spaced from a grounding core, whereby the strap will be enabled to carry a normal current without transmitting the latter to the grounding core, but when a high potential for eX'cessive current is imparted to the strap, said current, by reason of its potential, will leap the gap existing between the strap and the grounding core, so as to be conveyed by the latter to a point of safe discharge, thus enabling the instruments forming a part of said circuit, to be protected from injury.

A further object rests in a lightning arrester having the various elements comprising the same so inter-related, that in the event of one or more of the elements becom ing broken or damaged, the offending parts may be readily removed, and new parts substituted in place thereof, Withoutin any Way affecting the other elements of the arrester.

Other objects reside in an arrester of the above character, which will be reliable and efficient in operation, economically manu-` factured, capable of being readily and quickly assembled and of durablb and substantial construction.

The preferred embodiment of the invention is represented in the accompanying drawing, forming a part of this vspecification, in which similar characters of reference indicate like parts throughout the several views thereo l Figure 1 is a front elevation of 'a pair of coperating lightning arresters, constructed in accordance to the principles of the present invention. f l

Fig.'2 is a side elevation thereof.

.Fig a vertical longitudinal sectional i'iew taken along the line 3%3 of Fig. 1. Fig. 1 is a horizontal sectional view taken along the linac l--t of F ig.` 1.

'Fig 5 is a detail perspective view of the conductor strap.

Fig. 6 is a similar view of the grounding core.

Fig. 7 is a perspective view removable core elements. y

Fig. 8 is a diagrammatic view disclosing the arrester-s as applied to an electrical circuit.y i Referring more particularly to the drawing, in the preferred embodiment of my invention I employ a plurality of lightning arresters 1, each of which consists of an insulated base 2, upon which the elements of the arrester are mounted. and to provide means for facilitatingthe securingof the arresters to a wall or panel 3. To effect the securing of the arrester tothe wall, the base Q is provided with a plurality of vertically alined, spaced, countersunk openings 4, which are primarily adapted to receive securing elements 5, the latter being screwed into the wall 3, whereby the arrester will be rigidly secured in a working` position.

Binding. or terminal posts 6 and 7 are carried by each base 2, and are locatedin spaced relation. said posts being threaded to receive binding nuts 8, through the use ofwhich the arresters may be wired toan electrical yof one of the circuit. Each arrester is providedwith a conductor 9, .which is employed to bridge the gap existing between the posts 6 and 7. In this instance, the conductor is formed from arelatively flat strip ofmetal, having the medial portions thereof substantially7 arched, as at10. and havin the extremities thereof provided with openings, which openings are employed to receive the posts 6 and 7 whereby the terminals of the arrester will be connected for electrical communication. The conductors 9 are usually securedin position through the agency of the binding nuts` 8.

Positioned within the arched portions 10 of the conductors 9 are grounding cores 11, preferably formed from high-grade steel.

Each core is provided with aninwardly eX- tending stud 1'2. which is positioucdwthin an opening 13 provided in the central porposts 7,

tion of the base 2. The cores 11 are formed to provide annular grooves 11 for the reception of removable semi-circular plates 15, vvhich normally lie vvholly vvithin Said grooves, the imier plates being provided vvith openings 1G for the reception of the inwardly extending studs 12.

Interposed between the inner plates 15 and the bases 2 are plates 17, the latter being formed ivith openings 18 for the reception of the studs v12, and are further providedv vvith inivardly extending lugs 19, operable to engage with the members 2, so as to retain the plates 17 in fixed positions. It will be noted upon referring to Figs. 2 and 3 of the drawing that the margins of the plates 1T are slightly spaced from the conductors 9 yso as to define sparking gaps 2O therebetvveen. The grounding cores are further insulated from the conductors-9, through the provision of insulation strips 21, the latter surround the plates 15 and 'prevent the latter from engaging With the substantiallyY arched portions 1() of the conductors 9. The cores 11 are further provided with central threaded openings 22 which terminate at one end in enlarged bores 23, the latter being employed to receive thel extended bosses integrally formed upon one side of said cores. This construction enables the cores 11 to be electrically connected. A common grounding Wire may be readily connected vvith one extremity of the ,cores through the agency of a binding screvv 25, the latter being adapted to be threaded linto one of the openings 22, so as to frictionally bind said grounding vvire t the Cores.

In operation, the arresters 1 are set up in the multiple formation disclosed in Fig. 1,

\and are preferably positioned vvithin a housing or station 2G, and lead vvires 27 and 28, leading from any suitable source of -extraneous povver, are extended to-the arresters and are connected vvith the terminal posts 6 thereof. Other vvires 29 and 30 are similarly connected ivith the lovver binding and extend to a motor, or any other electrical instrument or device, mounted vvithin the station 26. Thus the motor circuit can be traced by ivay of the Wire 27 to the binding post (3, thence by one of the conductors 9 to the vvire 29. Then through the motor 31 to theivire 30, and from the wire` 30, by virtue of one of the conductors 9. to the vvire 28, thence to the negative side of a source of energy. Thus it Will be evident that under normal conditions the arresters 1 vvill not interfere vvith the progress current through the motor circuit above .lescribed. and that the space existing between the plates 17 and the conductors 9 and the insulating strips 21, will prevent said riff-uit from being short-circuited by the grounding core mechanism.

In the event of lightning` engaging ivith the vvires 27 and 28 so as to be conducted by the latter, the effects of this high-potential current vvill be prevented from engaging vvith the motor 31 through the provision of the arresters 1. This is due 'to the fact that vvhen an excessive current is being conveyed by the conductors 9, the same vvill jump the sparking gaps 20, so as to be conducted by the plates 17 and 15 to the grounding cores 11, from .vhich this excessive current is conveyed by means of a vvire 32 to a suitable ground 33. This feature, that is the jumping of an excess current. from the conductors 9 to the cores 11, is further insured by providing the marginal edges of the conductors 9 at points along the substantially arched portions 10 thereof, with a plurality of spaced notches 23, which leave fingers 35 projecting from the conductors. Said lingers extend beyond the edges of the strips 21, and overlie the removable plates 15. Thus if all of the excessive current carried by the conductors 9 should fail, for any reason, to be conveyed to the cores 11 by vvay of the plates 17, the same vvill leave the conductor along any of the positions defined by the fingers 35, as Will be clearly understood, said fingers being also employed to prevent current discharged from the conductors 9 to the cores '11, from jutting forth in sheet formation, but on the other hand insures a clean sharp spark between the said members.

From the foregoing it vvilld be seen that there is provided a device in vvhich the objects of the present vinvention have been achieved, and that allot' the advantageous features above mentioned are, among others, present. The device is reliable in every respect, capable of being economically manufactured, and in the event of any of the parts becoming broken or out of order, the same may be readily removed and nevv parts substituted in place thereof, without in any way affecting the remainingelements of the arrester. This is particularly true with reference to the copper plates 15, which receive the brunt of thev effects of lightning when transmitted -to the arrester, as when said plates are damaged they may be removed from the core Without necessitating the discarding of the latter. By forming the cores 11 from steel, the efficiency of the arrester is greatly enhanced, as lightning vvill endeavor to reach the cores by reason ofthe inherent lightning attractive properties of the steel cores.

As many changes could be made in the above construction, and'many apparently ividely different embodiments of this invention could Abe made Without departing from the scope thereof, it is intended that all Imatter contained in the above description, or shown in the accompanying drawings, shall be interpreted as illustrative, and not in a limiting sense.

Having described the invention what is claimed as new and patentable is:

r .11. A lightning arrester, comprising an insulated base, wiring terminals carried by fsaidfbase, a strap of conducting material loperable to bridge saidterminals, and having a substantially arch-shaped portion formed therein, and a grooved grounding core mounted upon said base and disposed within the arched portion of the strap, and a spacing member mounted in the groove of the core.

2. A lightning arrester, comprising an insulated base, circuit terminals carried by said base, a conductor operable to be associated with said terminals, said conductor having the medial portion thereof substantially arched, and a grooved grounding core shaped to conform to the arched portion of said conductor, and means arrangedin the groove of the corefor spacing the core from said conductor.

3. A lightning arrester, comprising a plurality of spaced wiring terminals having an insulated mounting, a conductor of rela'- tively flat strap-like formation operable to be connected with said terminals, a grounding element located contiguous to said conductor, but slightly spaced therefrom in order to define a sparking gap, and a removable plate section carried by said grounding element, and utilized to protect the latter from the effects of excessive currents.`

4. A lightning arrester, comprising a plurality of spaced wiring terminals having insulated mountings, a conductor of flat straplike formation operable to connect said terminals, the medial portion of said conductor being substantially arched and provided with a -series of fingers oh the edges thereductor, and located in spaced relation with 1- the latter, whereby an abnormal current passing through said conductor, will be transmitted-to said tially as described.

5. A lightning arrester, comprising an insulated base, wiring terminals secured to said base, a strap of conducting material adapted to be connected with said terminals, the medial portion of said strap being s ubstantially arched, and provided with serrated edges, a grounding core associated with said base, and disposed Within arched portion of said'strap, removable plates operable to fit-'within an annular groove formed in said core, and a plate interposed between said core and said base, and adapted to conduct excessive currents carried by said Strap to said plates and their cooperating core.

6. A hghtning arrester, comprising an insulated base, wiring terminals secured' to said base, a strap of conducting material adapted to be connected With said terminals, the medial portion of said strap being substantially arched, and provided with serrated edges, a grounding core aociated with said base, and disposedwithin arched portion of said strap, removable plates operable to t within an annular groove formed in said core, and a plate interposed between said core and said base, and adapted to conduct excessive currents carried by said strapy to said plates and their cooperating core, and binding means carried by said core, and operable to secure a grounding Wire thereto. In testimony whereof I aiix my signature.

FREDERICK H. BURKHART.

grounding' core, substan- 

